import java.util.Arrays;

public class Test {

    public static void func1(int[] array1) {
        array1=new int[10];
        System.out.println(Arrays.toString(array1));
    }

    public static void func2(int[] array2) {
        array2[0]=10;
        System.out.println(Arrays.toString(array2));
    }

    public static void main(String[] args) {
        StringBuilder stringBuilder=new StringBuilder("abcd");
        stringBuilder.reverse();
        System.out.println(stringBuilder);
    }





    public static void main3(String[] args) {
        long start = System.currentTimeMillis();
        String s = "";
        for(int i = 0; i < 10000; ++i){
            s += i;
        }
        long end = System.currentTimeMillis();
        System.out.println("String "+(end - start));

        start = System.currentTimeMillis();
        StringBuffer sbf = new StringBuffer("");
        for(int i = 0; i < 10000; ++i){
            sbf.append(i);
        }
        end = System.currentTimeMillis();
        System.out.println("StringBuffer "+(end - start));

        start = System.currentTimeMillis();
        StringBuilder sbd = new StringBuilder();
        for(int i = 0; i < 10000; ++i){
            sbd.append(i);
        }
        end = System.currentTimeMillis();
        System.out.println("StringBuilder "+(end - start));
    }












    public static void main2(String[] args) {
        System.out.println("admin"=="admin");
        System.out.println("Admin".toLowerCase()=="admin");
    }

    public static void main1(String[] args) {
        int[] array={1,2,3,4};
        func1(array);
        func2(array);
    }
}
